Peripheral arterial disease (PAD) affects an estimated 8 million people in the United States and 200 million people worldwide. The prevalence of PAD has grown by nearly 24% over the previous decade and is strongly associated with significant morbidity and mortality, leading some scientists to describe PAD as a ?global pandemic?. Chronic kidney disease (CKD) and older age are associated with higher risk for PAD. For example, while 4% of people aged 66-69 years without CKD have PAD, the prevalence in this age group with CKD increases to 19% and up to 32% in people with CKD ?85 years old. Moreover, lower extremity PAD can lead to impaired mobility, infections, and amputations?events that reduce quality of life by more than twice as much other serious cardiovascular events such as myocardial infarction or stroke. However, relatively little is known about PAD and its treatments compared with other cardiovascular diseases, particularly in older patients with pre-dialysis CKD. The overall aim of this two-year proposal is to provide a comprehensive overview of lower extremity PAD, its treatment strategies and outcomes in older patients with CKD who are not yet on dialysis. We plan to achieve our aims by leveraging the strengths of the Medicare 5% sample, a representative sample of older adults across all 50 states in the U.S. Our project, which is focused in older patients with CKD and PAD, has the following three Specific Aims: 1) to examine trends in PAD procedures and whether these trends differ by severity of CKD; 2) to evaluate patient-centered outcomes after a lower extremity revascularization or amputation; and 3) to evaluate whether recommended PAD medications are effective and safe in older patients with CKD. Results from this project will help to reduce current knowledge gaps about contemporary PAD treatment practices in older patients with CKD, and inform future prospective studies.